We shall continue our studies of congenital defects in steroidal biogenesis. In particular we wish to identify the heterozygotes and this matter has defied all attempts to date. We will use some newer methods we have devised to detect abnormal intermediary metabolites. Along these same lines, after our original discovery of the 3-beta- hydroxysteroid dehydrogenase wherein all cases died in infancy, there are now described less severe blocks with survival into later life at which the steroidal urinary profile changes. We should like to investigate the possibility that these changes are due more to alterations in peripheral metabolism than of basic adrenal function (other than the secretion of some cortisol, since in these the defect is clearly partial). In line with these studies we should like to continue our investigations into factors involved in the attainment of human puberty including studies of the secretions of growth hormone, gonadotropins, and sex hormones. Connected with these studies is our continued interest in a large number of children with pituitary deficiency. We first reported the occurrence of thyroid deficiency in these subjects after treatment with growth hormone and we should like to pursue this problem further.